Gear hobbing machine attachment



June 7, 1949. w, BARQUS 2,472,644

GEAR HOBBING MACHINE ATTACHMENT Filed March 17, 1945 3 Sheets-Sheet 1June 7, 1949. J. w. BARCUS GEAR HOBBING MACHINE ATTACHMENT 3 Shets-Sheet 2' Filed March 17, 1.945

fWfBar cus x mm June '7, 1949.

Filed March 17, 1945 J. w. BARcu GEAR HOBBING MACHINE ATTACHMENT k I sSheets-Sheet s c/IWBaraus Patented June 7, 1949 UNITED STATES PATENTOFFICE GEAR HOBBING MACHINE ATTACHMENT John W. Barcus, Baltimore, Md.,assignor of fifty per cent to N. R. Kneass, Baltimore, Md.

14 Claims. 1

This invention relates to gear hobbing machines, and more particularlyto an attachment by means of which spherical gears may be cut on a.conventional hobbing machine.

An object of this invention is to provide a simple attachment which canbe mounted on a conventional bobbing machine of the type wherein thecutter is movable in both vertical and horizontal planes by hydraulic orother operating means, so that spherical gears may be cut on suchmachine.

Another object of this invention is to provide in combination with agear hobbing machine means whereby the cutter is shifted in its movementthrough the blank or workpiece in a manner to provide for sphericalcutting on the surface of the workpiece.

A further object of this invention is to provide a device of this kindwhich can be mounted on a hydraulic hobbing machine without change inthe present parts of the machine, the device being of simpleconstruction. and of sufiicient strength to eliminate undue strains ortorsion, and provide for the accurate cutting of the teeth in the gearblank.

A further object of this invention is to provide a device of this kindwhich can be accurately adjusted, so that gears of various diameters canbe accurately out.

A further object of this invention is to provide a device of this kind,which will permit rapid cutting of gears without frequent setting of theparts so that mass production can be accomplished.

To the foregoing objects and others which may hereinafter more fullyappear, the invention consists of the novel construction, combinationand arrangement of parts, as will be more specifically referred to andillustrated in the accompanying drawings, but it is to be understoodthat changes, variations, and modifications may be resorted to whichfall within the scope of the invention as claimed.

In the drawings:

Figure 1 is a detail side elevation, partly broken away and in section,of a conventional gear hobbing machine of the hydraulic type. havingmounted thereon a spherical gear forming means constructed according toan embodiment of this invention.

Figure 2 is a fragmentary sectional view taken on the lin 22 of Figure1.

Figure 3 is a detail side elevation of the a justable linkage.

Figure 4 is a fragmentary sectional view taken on the line 44 of Figure1.

Figure 5 is a fragmentary sectional view taken on the line 5-5 of Figure1.

Figure 6 is a sectional view taken on the line 6-6 of Figure 4.

Figure 7 is a sectiona1 view taken on l'! of Figure 4.

Figure 8 is a diagrammatic view showing the operation of the device.

Figure 9 is a sectional view taken on the line 9-9 of Figure 1.

Referring to the drawings, the numeral l0 designates generally a hobbingmachine, including a bed I I, having a horizontally disposed guide ortrack l3 on which an upright carriage support i2 is slidably mounted.The carriage support I2 is movable lengthwise of the track or guide I3by hydraulic or other power means (not shown). The support I! hasslidable on the forward side 14 thereof a carriage l5, which isvertically movable by hydraulic, mechanical, or other suitable powermeans.

An upright standard I6 is secured to the bed, or base H, at the forwardend thereof and has extending therefrom a supporting arm ll, having aholding member l8 secured thereto for rigidly holding the upper end of ashaft, spindle, or the like. The bed, or base II, has rotatably mountedthereon a work support [9, which is rotatable about a vertical axis. Thecarriage l5 has mounted thereon a rotatable spindle 20, on which a gearhob 2| is adapted to be secured for cutting teeth in a blank workpiece22, which the line is secured to the work support l9. At the presenttime the workpiece 22 is a blank gear, which is formed with a sphericalperipheral surface 23, and the gear formed from the workpiece 22 issimilar to the gear shown in my prior Patent No. 2,302,813, datedDecember 1, 1942.

In order to provide a means whereby the hob, or cutter 2!, will beadjusted as it is rotated in order to cut spherical teeth in theperiphery of the blank 22; I have provided an adjustable linkstructurewhich is connected to the bed and the carriage support l2, soas to shift the support !2 rectilinearly simultaneously with thevertical movement of the carriage [5.

There is a linkage, generally designated by the numerals 24 and 25, oneach side of the hobbin machine and the detail description of onelinkage will apply equally as well to the other. The linkage 24 includesan elongated threaded shaft 26, which is formed with square threadsextending substantially throughout the length thereof.

and the shaft 26 is formed with a reduced diameter portion 21 adjacentone end thereof, which is journalled in a block, or mounting, 28.

A bearing sleeve 29 is disposed about the shaft portion 21 within theblock 28. The shaft portion 21 is held against endwise movement withrespect to the block 28 by means of an annular nut 36, which is threadedon a reduced stud 3| formed on the shaft portion 21. An annular collaror flange 32 is formed integral with the adjacent end of the threadedshaft 26 and bears. against the side of the block 28 oppositely from thenut 30. The nut 30 is locked on the stud 3| by means of a set screw 33,The shaft 26 is also formed with a square stud 34 extending from thestud 3|, and a shaft rotating wheel 35, having a hub 36 formed witha'sq'uare bore 31, en gages about the square stud 34.

A nut 38 is threaded. on a reduced threaded stud 39, extending from thesquare stud 34, and a washer 48 'is'interposed between the nut 38 andthe adjacent end of the hub 36. An index plate 4|, having a hub or boss42 formed with a square bore, ismounted on the square stud 34 betweenthe inner end of 'the hub 36 and the outer end of the nut 30. The indexmember 4| is provided with a tapered outer side 43, having graduation 44thereon which are correlated with a pointer, or mark, 45 carried by theblock 28.

The block 28 has extending laterally thereof a stud 46, which has abushing 41 engaging thereabout, and the bushing 41 is mounted in avertically disposed supporti'ngplate 48. The stud 46 is rockably securedwith respect to the plate 48 by means of a plate, or washer, 49 securedto the inner end of the stud 46 by means of a screw 50. The supportingplate 48 is secured to one side of the bed I I by means offast'eningmembers |,and is disposed in a position whereby the axialcenter of the stud 46 will be disposed in the same plane asthe axialcenter of the workpiece 22.

The shaft 26 is threaded through a nut, or block, 52 which is adjustablysecured to the carriage I5, as will be hereinafter described.

The nut or block 52 has formed integral therewith a stud 53, having abushing 54 disposed 'thereabout, and is rotatably mounted in a bearing55. A spacing washer 56 may be interposed between the bearing 55 and theadjacent, or inher side of the nut 52, so as to position the nut '52 inthe desired spaced relation with respect to the carriage I 5. The stud53 is held against endwise movement with respect'to the bearing 55 bymeans of a plate, or washer, 51 secured to the -inner end of the stud5:3 by means of a bolt or screw 58.

'The bearing 55 has extending vertically upwardly therefrom a threadedshaft, or support, '59. The shaft 59 extends through a bore 60 formed ina block'BI, having flanges 62 secured by fastening members 63 to theside of the carriage I5. The axis of the stud 53 may be disposed belowthe horizontal axis of the hob 2| and spindle 20, and preferably theshaft 26 is in a'horizontal position when the axial center of the hob"2|is inthe horizontal plane of the cen- -ter of the workpiece -22.

The bearing supporting shaft "59'is vertically adjusted and locked in"its vertically adjusted position by-meanspf nuts-63 and 64 threaded onthe shaft 59 and engaging about the opposite ends of the supportingblock or member 6|.

*In' the-useand operation of this invention the two plates *48 aremounted on opposite sidesof the bed *or base -l=l "in 'a -=position"whereby axial 4 centers of the studs 46 will be in the plane of thevertical axis of the work support I9 and the workpiece 22. The blocks ormountings 6| are secured to the opposite sides of the hob carriage I5,and the nuts 52 are vertically adjusted so that the longitudinally axisof the screw shaft 26 will be in a horizontal plane at the same timethat the axial center of the hob spindle 20 is in the same horizontalplane as the horizontal center or axis of the workpiece 22.

Referring to Figure 8 of the drawings, the hob 2| is raised to a pointjust above the upper end of. the workpiece 22. At this time the screwshaft 26, which is shown in full line in Figure 8, will be upwardlyinclined. As carriage I5 moves downwardly,'the carriage supportingmember I2 will be shifted horizontally, so that the hob 2| will move onan arc, having as a center the center of the workpiece 22. The hob 2|will move downwardly to substantially the position shown by the dot anddash line in Figure 8, and atthis time the screw shaft or link 26 willswing downwardly with the stud, as a pivot to thedot and dash lineposition. The carriage support l2 will initially move away from theworkpiece 22 to the limit shown by the dot and dash line in Figure 8.and will then be moved toward the workpiece to the full line positionshown inFigure 8.

Thi structure may be formed as an attachment for a conventional gearbobbing machine, particularly of the type having a horizontallyshiitable carriage support, orstanchion, for the hob carriage. Theprovision of the-screw shaft 26- permits initial adjustment of thesupport, or stanchion, I2 so as to pe mit cutting blanks of difierentdiameters, This device will operate on machines which cut teeth in theblanks in either one or more traverses of the hob. The screw shaftsprovide a means whereby the depth of the cut formed in the blank by thehob can be adjusted, as may be desired.

The exact configuration illustrated is regarded s the pt mum. but someof the desirabl r sults inherent in thi disclosure may be obtained byvarious slight modifications including some departure from the exactconfiguration shown, and it is therefore requested that the scope of theinvention should be regarded as limited only by the terms of the claims.

What I claim is:

1, In combination, a gear bobbing machine including a stationary bed. ahor zontally slidable stanchion carried by said bed, a verticallys1idable carriage carried by said stanchion, a pair of links, and meanspivotally connecting said links together, means pivotally securing oneof said links to said bed, andmeans securin the other of said links tosaid carria e whereby s d stam chion will move horizontally withvertical movemerit of said carriage said lattermeans including mean fordjustin aid other l n means n s wise.

2. In a gear hobbing machine havin a, stationary bed, a horizontallymovable stanchion and a vertically movablehob carriage, an at tachmentfor' said machine whereby to out spherical gears, comprising a pair ofpivotally connected together links, means pivotally con; necting one ofsaid links to said bed and means fixedly securing the other of 'saidlinks to said carriage whereby to effect horizontal movement of saidstanchion simultaneous with the vertical movement of said carriage. w

3. In a gear hobbing machine as set forth in claim 2 wherein said pivotmeans is adjustable in a manner to vary the spacing between the Pivots.

4. In a gear hobbing machine having a stationary bed, a horizontallymovable stanchion and a vertically movable hob carriage on saidstanchion, an attachment for said machine whereby to cut arcuate teethcomprising a part adapted for attachment to said carriage, a second partadapted for connection to said bed, and a pivoted connection betweensaid parts and said bed.

5. In a gear hobbing machine having a stationary bed, a horizontallymovable stanchion on said bed and a vertically movable hob carriage onsaid stanchion, an attachment for said machine comprising a pair ofpivotally connected together elongated members, and means connectingsaid members to said bed and said carriage in a manner whereby verticalmovement of said carriage will eiTect horizontal movement of saidstanchion.

6. In a gear hobbing machine having a stationary bed, a horizontallymovable stanchion on said bed and a vertically movable hob carriage onsaid stanchion, an attachment for said machine comprising a pair ofpivotally connected together members, and means mounting said members onsaid bed and carriage whereby vertical movement of said carriage willefiect positive movement of said stanchion in either direction.

'7. In a gear hobbing machine having a stationary bed, a horizontallymovable stanchion on said bed and a vertically movable hob carriage onsaid stanchion, an attachment for said machine comprising a pair ofpivotally connected together elongated members, means adjusting saidmembers endwise, and means connecting said members to said bed and saidcarriage in a manner whereby vertical movement of said carriage willeiT-ect horizontal movement of said stanchion.

8. An attachment for a milling machine having a stationary bed, ahorizontally movable stanchion on said bed and a vertically movable hobcarriage on'said stanchion, said attachment comprising a pair ofpivotally connected members, and means securing said members to said bedand said carriage whereby vertical movement of said carriage will effectpositive rectilinear movement of said stanchion in either direction.

9. An attachment for a milling machine having a stationary bed, ahorizontally movable stanchion and a vertically movable hob carriage onsaid stanchion, said attachment comprising a pair of threaded elongatedmembers, a part threaded onto one of said members, means pivotallyconnecting said part to the other member, means rotatably securing saidone member to said bed, a second part fixed to said carriage, and meansadjusting the endwise position of said other member relative to saidsecond part Whereby vertical movement of said carriage will effecthorizontal movement of said stanchion.

10. In combination, a gear cutting machine including a stationary bedmember, a stanchion horizontally movable on said member, a carriagemember vertically movable on said stanchion, and pivotally connectedmeans secured together and to both of said members for effectingpositive rectilinear movement of said stanchion in either direction uponvertical movement 01" said carriage member.

11. In combination, a gear cutting machine including a stationary bedmember, a stanchion horizontally movable on said member, a carriagemember vertically movable on said stanchion, a pair of pivotallyconnected together elements, mean-s swingably securing one of saidelements to one of said members, and means fixedly securing the other ofsaid elements to the other of said members.

12. In combination, a gear cutting machine including a stationary bedmember, a stanchion horizontally movable on said members, :a carriagemember vertically movable on said stanchion, a pair of elongatedthreaded elements, a block pivotally carried by one of said elements andformed with a threaded opening through which the other elementthreadedly engages, means swingably and rotatably supporting said otherelement from one of said first named members, and means securing saidone element to the other of said elements whereby said one element maybe adjusted endwise, vertical movement of said carriage effectinghorizontal movement of said stanchion.

13. In a gear hobbing machine having a stationary bed, a horizontallymovable stanchion on said bed and a vertically movable hob carriage onsaid stanchion, an attachment for said machine whereby to cut arcuateteeth comprising a part for attachment to said carriage, a second partfor attachment to said bed, a pair of threaded links connecting saidparts, a nut for one of said links pivotally carried by one of saidparts, and a bearing block fixedly carried by the other part throughwhich the other link extends.

14. In a gear hobbing machine attachment as set forth in claim 13including means adjustably supporting said other link from said bearingblock.

JOHN W. BARCUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,639,624 Woltzendorff Aug. 16,1927 2,315,068 Matthews Mar. 30, 1943

